ABSTRACT Support is requested for a Keystone Symposia conference entitled Respiratory Viruses: New Frontiers organized by Drs. Kanta Subbarao, JoAnn A. Suzich and Carolina B. Lpez. The conference will be held in Banff, Alberta, Canada from February 5-9, 2021. Respiratory viruses continue to pose medical challenges. The lung is susceptible to infection by multiple viruses each with unique mechanisms of interacting with the human host and evading the immune system. Respiratory infections are relatively easy to contract and are associated with significant morbidity and mortality. Despite many years of study, our ability to prevent and treat these infectious is limited. This Keystone Symposia conference will focus on novel insights into respiratory virus biology that may ultimately lead to more effective prevention and treatment strategies. In many cases, these novel insights are made possible by new tools that are now available to study pathogens whose infectious cycle is largely restricted to the airways ? making visible what was previously invisible. New information about virus host interactions will be discussed, as well as the interplay among diverse organisms present in the host airways. The long-term ramifications of respiratory virus infections beyond acute disease will be explored along with both recent successes and failures in prevention and treatment. This conference is a joint symposium with Viral Immunity: Basic Mechanisms and Therapeutic Applications and will have a few combined sessions. Finally, our conference will bring together scientists studying different respiratory viruses using diverse approaches from the perspective of the pathogens and host, recognizing that it is at the intersection of disciplines where opportunities for innovation and novel insight lie.